Improve the `scripts/review_apps/automated_cleanup.rb` script

From @caalberts:

This API looks like returning all deployments to date. If so, it will only grow in size over time.

The first deployment in https://gitlab.com/api/v4/projects/278964/deployments?per_page=100&page=1 was created in 2017.

Maybe we need to change the script to walk through matching review* environments and then delete deployments from there.

We should at least sort deployments by desc (default is asc) etc. See https://docs.gitlab.com/ee/api/deployments.html.